Refrigerating apparatus



Nov." 7, 1933. R. D. M INTOSH REFRIGERATING APPARATUS Filed Jan. 2, 1932 .NN Q. W j r W: E

Patented Nov. 7, 1933 REFRIGERATING APPARATUS Robert D. McIntosh, River Forest, 111., assignor to The Imperial Brass Manufacturing Company, Chicago, 111., a corporation of Illinois Application January 2, 1932. Serial No. 584,468

16 Claims.

My invention is concerned with refrigerators, designed primarily for household use, in which the liquid refrigerant, such as $02, is pumped by a compressor into an evaporator, where the entrance of the liquid supply is controlled by a float valve, and a layer of. lubricating oil covers the liquid refrigerant so that gas being drawn oif will not bubble up explosively through the liquid refrigerant so as to carry some of the m liquid with it into .the vapor return pipe and cause a frost back, that is highly objectionable.

One method of assuring that this oil layer is of the proper depth to operate efliciently is to provide adjustable means for controlling the 1 level of its upper surface, so that if on account of the level of the liquid refrigerant getting too high in the evaporator, the depth of the oil layer becomes too small to control properly the rising of the refrigerant vapor therethrough, the level 5 of its upper surface may be raised so as to increase the depth of the oil layer without having to change the range of movement of thefioat which controls the entry of the liquid refrigerant into the evaporator, and my present invention is concerned with simple mechanism constituting such adjustable means.

It is further concerned with such means that is also capable of adjustment so that in transportation the valve cannot be violently forced 39 into contact with its seat by its float-valve connections in case said float valve be accidentally thrown into an abnormal position.

It is further concerned with such means that can be operated from the exterior of the evap- 35 orator, and without the necessity of opening up the evaporator to get at the means that is located therein.

To these ends, it consists of the simple construction hereinafter fully described in detail w and particularly pointed out in the claims.

To illustrate my invention, I annex hereto a sheet of drawing, in which the same reference characters designate identical parts in all the figures, of which,- 4

p5 Fig. 1 is a central vertical section through the evaporating chamber, with the rest of the system indicated diagrammatically; and

Fig. 2 is a detail in section, on an enlarged scale, on the line 2-2 of Fig. 1.

in Referring to the drawing, the numeral designates, in general, an evaporator, comprising a header or container 21 forming a reservoir for liquid refrigerant, such as S02, and from which header depends a plurality of refrigerantconveying ducts 22 for conveying the refrigerant to the zone or place to be refrigerated. Refrigerant is delivered to the header through a reirigerant-conveying pipe 24, and is withdrawn through a vapor pipe 25. The pipe 24is con- 319 nected with a receiver 27, and the pipe 25 is connected to the low-pressure side of a compressor 30, preferably, as shown, to the crank case thereof. The high-pressure side of the compressor is connected with a condenser, which in turn is connected with the receiver 27. The compres- 65 sor is here shown as driven by a motor 33, which is controlled in response to the pressure within the pipe by means of an automatic switch 34 which connects the motor with the power mains 35.

The header 21,- which is herein shown as a refrigerant-containing chamber, may be formed of a drawn sheet-metal tube having one end thereof open, which receives a ring 40 which is suitably sealed in position. A head or valve plate 42 is secured to the ring 40 by the screws 43, and carries shut-off valves 44 and 45 which are connected, respectively, with pipes 24 and 25. The head 42 is provided with a passage 4'7 communicating with the valve 45, and carries an inwardly extending and upwardly sloping tube 48 for conveying gaseous refrigerant from the free space above the liquid in the refrigerating chamber. The head 42 is also provided with a passage 49 communicating with the valve 44 and having screwed into the inner end thereof the valve-seat member 50 having the passage 51 therethrough, which has the reduced end forming the seat 52 for .the needle valve 53 moving through an aperture 54 in an extension 55 of the valve-seat member 50, and pivoted in a recess 56 of the float lever 57, the forked end of which is fulcrumed by the pin 58 on the ear 59 forming a part of the extension 55, so that as the float 60 falls below the level shown in the drawing, the valve 53 will be opened to admit the liquid refrigerant to the evaporator, and closed when it rises. I

I The tube 48 has rotatably mounted thereon aneccentrically placed cylinder 61 closed at both ends except for the opening 62 in its inner end to admit the lubricating oil from the layer 63,

' the oil thus admitted being pressed into the tube 48 through the opening 64 in its under side, when the oil level is above said opening 64, so that it controls the oil level when the cylinder 61 is turned so that the opening 64 isbelow or even with the opening 62. If it is turned so as to bring the opening 62 above said opening 64, as indicated in dotted lines in Fig. 2, the oil level will be determined by the position of the bottom of the opening 62, and by turning this cylinder 61, the oil level can be adjustedin any desired position between the two extremes provided for.

To turn this cylinder from the outside of the 115 evaporator, I provide the shaft 65 journaled in the head 42 and provided with the packing 66 and the packing nut 67 screwed into the head 42 to prevent leakage along the shaft, which has the groove 68 in its outer end, to which a screw- 12 while in the vapor pipe 25.

driver or similar implement may be applied after the cap nut 69 has been unscrewed from the position shown in the drawing. The inner end of the shaft 65 has secured thereon the spur gear wheel '70 which meshes with the spur gear wheel 71 secured on the end of the cylinder 61 and separated from the inner face of the head 42 by the washer 72, the outer end of the cylinder 61 preventing any inward movement of the shaft 65 by its contact with the pinion '70. A helicallycoiled expanded spring 73 surrounding the tube 48 between the annular abutment 74 secured on the tube 48 and the similar abutment '75 loose on the tube and engaging a washer 76 between it and the adjacent end of the cylinder 61, prevents any substantial longitudinal movement of the cylinder on the tube 48.

The operation of the apparatus will be apparent from the foregoing description. Assuming that the cylinder 61 is adjusted in the extreme position shown in Fig. 1, which is that intended for shipment, with the projection 77 formed on the float lever 57, said projection will engage the adjacent portion of the cylinder 61 and prevent any excessive movement of the float 60 that would tend to jam the needle valve 53 in its seat 52, and which might otherwise occur in shipment. When it is installed, the service man will apply a gage to the vapor pipe 25, and having removed the cap nut 69, he will apply a screwdriver or similar tool to the groove 68 in the shaft 65, and turn it in either direction until the cylinder 61 is moved sumciently to clear the projection 77 and allow the valve 53 to close. The motor is then started and the apparatus allowed to run until the temperature is reduced sufiiciently to gage properly its action by observing the pressure in the vapor pipe. If before the proper pressure is obtained, there should be a frost back on the vapor pipe, that will indicate that the layer 63 of lubricating oil is not deep enough, and that some of the liquid refrigerant '78 is by the agitation of the gaseous refrigerant rising therethrough, being carried into the tube 48, thus causing the frost back by expanding into gas The shaft 65 will then be turned sufiiciently to bring the aperture 62 up toward the position shown in dotted lines in Fig. 2, or possibly even higher if needed, so that the oil can accumulate to the higher level and not be drawn off before the desired thickness of the layer is obtained, and which thickness will prevent any of the liquid refrigerant being carried into the open end of the tube 48. When the proper adjustment is obtained, as indicated by the pressure gage, the cap nut 69 can be replaced, and the device left to function normally. If, for any reason, the oil layer should get too thin, so that a frost back occurs, the cap nut 69 can be removed and the cylinder 61 turned to bring the aperture 62 still higher and increase the thickness of the oil layer until the frost back is eliminated and the apparatus once more func- .tions as intended.

While I have herein shown and described my invention as embodied in the form which I at present consider best adapted to carry out its purposes, it will be understood that it is capable of modifications, andthat I do not desire to be limited in the interpretation of the following claims except as may be necessitated by the state of the prior art.

What I claim as new, and desire to secure by Letters Patent of the United States, is:

1. In a refrigerating system, the combination with an evaporating chamber therein adapted to be partially filled with liquid refrigerant upon which is superimposed a layer of lubricating oil, of an outlet pipe therein connected to a vapor pipe and having its main inlet for the gaseous refrigerant above the level of the oil and an opening therein through which oil may enter the pipe, an inlet for liquid refrigerant, a float valve for controlling the entry of the liquid refrigerant through said inlet, and means to vary the level of the top of the oil layer.

2. In a refrigerating system, the combination with an evaporating chamber therein adapted to be partially filled with liquid refrigerant upon which is superimposed a layer of lubricating oil, of an outlet pipe therein connected to a vapor pipe and having its main inlet for the gaseous refrigerant above the level of the oil an opening therein through which oil may enter the pipe, an inlet for liquid refrigerant, a float valve for controlling the entry of the liquid refrigerant through said inlet, and means operable from the exterior of the evaporating chamber to vary the level of the top of the oil layer.

3. In a refrigerating system, the combination with an evaporating chamber therein adapted to be partially filled with liquid refrigerant upon which is superimposed a layer of lubricating oil, of an outlet pipe therein connected to a vapor pipe and having its main inlet for the gaseous refrigerant above the level of the oil and an opening therein through which oil may enter the pipe, an inlet for liquid refrigerant, a float valve for controlling the entry of the liquid refrigerant through said inlet, and means to vary the level of the top of the oil layer and to prevent the possible engagement of the float valve with its seat while the chamber is being shipped.

4. In a refrigerating system, the combination with an evaporating chamber therein adapted to be partially filled with liquid refrigerant upon which is superimposed a layer of lubricating oil, of an outlet pipe therein connected to a vapor pipe and having its main inlet for the gaseous refrigerant above the level of the oil and an opening therein through which oil may enter the pipe, an inlet for liquid refrigerant, a float valve for controlling the entry of the liquid refrigerant through said inlet, and means operable from the exterior of the evaporating chamber to vary the level of the top of the oil layer and to prevent the possible engagement of the fioat valve with its seat while the chamber is being shipped.

5. In a refrigerating system, the combination with-an evaporating chamber therein adapted to be partially filled with liquid refrigerant upon which is superimposed a layer of lubricating oil, of an outlet pipe therein connected to a vapor pipe and having its main inlet for the gaseous refrigerant above the level of the oil and an opening therein through which oil may enter the pipe, an inlet for liquid refrigerant, a float-controlled needle valve for permitting the entry of the liquid refrigerant through said inlet, a float, a lever con necting said float with said needle valve, and an eccentric abutment mounted to rotate on said outlet pipe and movable thereon to a position where it will be engaged by the lever and prevent possible engagement of the needlevalve with its seat. v

6. In a refrigerating system, the combination with an evaporating chamber therein adapted to be partially filled with l'quid refrigerant upon which is superimposed a layer of lubricating oil, of an outlet pipe therein connected to a vapor pipe and having its main inlet for the gaseous refrigerant above the level of the oil andan opening therein through which oil may enter the pipe,

' an inlet for liquid refrigerant, a float-controlled needle valve for permitting the entry of the liquid refrigerant through said inlet,,a float, a lever connecting said float with said needle valve, an eccentric abutment mounted to rotate on said outlet pipe and movable thereon to a position where it will be engaged by the lever and prevent possible engagement of the needle valve with its seat, a shaft joumaled in the head of the evaporating chamber and rotatable from the exterior thereof, and gearing connecting the inner end of the shaft and the abutment.

7. In a refrigerating system, the combination with an evaporating chamber therein adapted to of an outlet pipe therein connected to a vapor pipe and having its main inlet for the gaseous refr'gerant above the level of the oil and an opening therein through which oil may enter the pipe, an inlet for liquid refrigerant, a float-controlled needle valve for permitting the entry of the liquid refr'gerant through said inlet, a float, a lever connecting said float with said needle valve, an eccentric abutment mounted to rotate on said outlet pipe and movable thereon to a position where it will be engaged by the lever and prevent possible engagement of the needle valve with its seat, a shaft journaled in the head of the evaporating chamber, gearing connecting the inner end of the shaft and the abutment, and means on the I outer end of the shaft for turning it.

trolled needle valve for permittingthe entry of the liquid refrigerant through said inlet, a float, a lever connecting said float with said needle valve, an eccentric abutment mounted to rotate on said outlet pipe and movable thereon to a position where it will be engaged by thelever and prevent possible engagement of the needle valve with its seat, a shaft joumaled in the head of the evaporating chamber, gearing connecting the inner end of the shaft and the abutment, means on the outer end of the shaft for turning it, and

a cap nut to cover the outer end of the shaft.

9. In a refrigerating system, the combination with an evaporating chamber therein adapted to be part ally filled with liquid refrigerant upon which is superimposed a layer of lubricating oil,

of an outlet pipe therein connected to a vapor pipe and having its main inlet for the gaseous refrigerant above the level of the oil and an open ing therein through which the oil may enter the pipe and a hollow cylinder eccentrically mounted on the outlet pipe and enclosing the oil opening thereof and having'an oil opening in itself.

10. In a refrigerating system the combination with an evaporating chamber therein adapted to be partially filled with 'liquid refrigerant upon which is superimposed a layer of lubricating oil, of an outlet pipe therein connected to a vapor pipe and having its main inlet for the gaseous refrigerant above the level of the oil and an opening therein through which the oil may enter the pipe, a hollow cylinder eccentrically mounted on the outlet pipe. and enclosing the oil opening thereof and having an oil opening in itself, and means for rotating said cylinder from the exterior of the evaporating chamber.

11. In a refrigerating system, the combination with an evaporating chamber therein adapted to be partially filled with liquid refrigerant upon which is superimposed a layer of lubricating oil, of an outlet pipe therein connected to a vapor pipe and having its main inlet for the gaseous refrigerant above the level of the oil and an opening therein through which the oil may enter the pipe, a hollow cylinder eccentrically mounted on the outlet pipe and enclosing the oil opening thereof and having an oil opening in itself, and means for rotating said cylinder from the exterior of the evaporating chamber consisting of a shaft joumaled. in the head of the evaporating chamber, and gearing connecting the shaft and the hollow cylinder. I

12. In an evaporator for refrigerating apparatus, the combination with a valve, of a float for actuating said valve, an outlet pipe connected to a vapor pipe, an inlet opening for oil into said pipe, and means operable from the exterior of the evaporator to determine the level at which the' oil may enter said pipe.

13. In an evaporator for refrigerating apparatus, the combination with a valve, of a float for actuating said valve, an outlet pipe connected to a vapor pipe, an inlet opening for oil into said pipe, and a hollow cylinder joumaled on the outlet pipe and surrounding the inlet opening and also having an oil inlet by which the level of the oil may be regulated.

r 14. In an evaporator for refrigerating apparatus, the combination with a valve, of a float for actuating said valve, an outlet pipe connected to a vapor pipe, an inlet opening for oil into said pipe, a hollow cylinder journaled on the outlet pipe and surrounding the inlet opening and also having an oil inlet by which the level of the oil may be regulated, a shaft joumaled in the head of the evaporator, and gearing connecting the inner end of the shaft with the adjacent end of the cylinder.

15. In an evaporator for refrigerating apparatus, the combination with a valve, of a float for actuating said valve, a lever connecting the float and the valve, an outlet pipe connected to a return pipe having an inlet opening therein for oil, and an adjustable abutment joumaled on said outlet pipe movable into .or out of a position where it will be contacted 'by the lever to prevent the valve being moved into contactv with its seat and also having means-to determine the oil level.

16. In an evaporator for refrigerating apparatus, the combination with a valve, of a float for actuating said valve, a lever connecting the float and the valve, an outlet pipe connected to a return pipe having aninlet opening therein for. oil, and a hollow cylinder journaled on the outlet pipe and surrounding the inlet opening and also having an oil inlet by which the level of the oil may be regulated and also movable into or out 

